Heart rate asymmetry follows the inspiration/expiration ratio in healthy volunteers

Abstract

Heart rate asymmetry (HRA) quantifies the uneven distribution of points above and below the identity-line in a Poincaré plot of RR-intervals. The authors investigated if HRA could be influenced by the inspiration/expiration ratio. Healthy volunteers (n = 18) were studied in the supine position at 4.5 s metronome breathing. ECG and breathing signals were recorded for 360 s at each breathing pattern: inspiration controlled, inspiration/expiration controlled (1:2, 1:1, 2:1 ratio), inspiration controlled again. Time domain, frequency domain and Poincaré plot heart rate variability (HRV) analysis with Porta's and Guzik's indices were performed on 300 s tachograms. There were no statistically significant differences in time domain, frequency domain and standard Poincaré plot parameters during the various breathing patterns, whereas Porta's and Guzik's indices significantly rose at 1:1 and 2:1 compared to physiological 1:2 breathing. There were no significant differences in the HRA parameters between the first and the last runs. In our population the inspiration/expiration ratio significantly influenced HRA, but not standard HRV parameters. Positive correlation of Guzik's and Porta's index reflects reciprocal changes of the number of points and their dispersion in the accelerating and decelerating sets of RR-intervals. HRA-analysis can be a promising method for investigating cardiovascular regulation/health particularly with further spreading of wearable monitors.

Controlling the Inspiration/Expiration Ratio Benefits the Deceleration Capacity Index of Heart Rate in Assessing the Sympatho:vagal Balance

“…Figure 3 shows that the HRA increases monotonously with the elevation of the I/E ratio. When the I/E ratio was modified from 1:2 to 2:1, PI increases from 42.7 ± 2.7% to 63.7 ± 2.3%, and GI increases from 45.3 ± 2.1% to 61.5 ± 2.0%, in agreement with the reported physiological experiments [6,7]. …”

“…The frequency range is 0.04 to 0.15 Hz for the LF component and 0.15 to 0.4 Hz for the HF component. The ability of the model in simulating the HRA phenomenon was validated by checking whether the relationship between the HRA and the I/E ratio agrees with the experimental findings [6,7].…”

“…It implies that the performance of DC can be improved by adjusting the HRA level. As the inspiration/expiration (I/E) ratio influences the HRA level [6,7], we attempted to analyze whether controlling the I/E ratio benefits DC in assessing the ANS activity.Our study was conducted based on a cardiovascular system model. The model can produce a set of RRI time series with controlled levels of ANS activity for DC calculation.…”

Multistructure index characterization of heart rate and systolic blood pressure reveals precursory signs of syncope

“…Typically, heartbeats are shortened (heart rate accelerates) during inspiration, and prolonged (heart rate decelerates) during expiration. However, the exact phase relationship happens to be dependent on the respiration rate 18, 20, 30 . Therefore, a paced breathing protocol at frequency 0.25 Hz was applied to our subjects with the physiological ratio of 1:2 inspiration to expiration.…”

“…HRV analyses have revealed a difference in the short-term organization between heart decelerations and accelerations 10–16 . Moreover, it has been proposed that this difference could be related to the rate 17–19 , and the pattern of breathing 20 . Also by studying BPV, differences between rises and falls in systolic blood pressure have been identified 21 .…”